Android Build Failure: Powersync_flutter_libs SDK Update

Android Build Failure: Updating powersync_flutter_libs to Android SDK 36

Android build errors can be frustrating, especially when they halt your project's progress. This article addresses a common issue where a Flutter project using the powersync_flutter_libs package fails to build due to an outdated Android SDK. Specifically, the error arises because the package is compiled against an older version of the Android SDK (API level 32), while the dependencies it relies on require a more recent one (API level 34 or higher). This mismatch leads to build failures and necessitates an update to the powersync_flutter_libs package to resolve the conflict and ensure a successful build.

The Problem: Outdated SDK in powersync_flutter_libs

The core of the problem lies within the powersync_flutter_libs package itself. As the error logs indicate, the package is built using an older Android SDK version, specifically API level 32. This means that when the project tries to integrate this package, it clashes with the requirements of the newer dependencies such as androidx.fragment:fragment, androidx.window:window, and others. These dependencies demand a minimum compile SDK version of 34 or higher, resulting in the build failing. This is a common issue as Android development evolves, and libraries are updated to take advantage of the latest Android features and APIs.

Understanding the Error Messages

Let's break down the error messages to understand why this is happening. The error messages explicitly state that the dependencies within powersync_flutter_libs require a newer compileSdk version. The compileSdk in the build.gradle file of the powersync_flutter_libs package determines the Android API level against which the package is compiled. The error messages point out specific dependencies like androidx.fragment:fragment:1.7.1 and androidx.window:window:1.2.0 that require a compileSdk of at least 34.

The error messages also highlight the difference between compileSdk, targetSdk, and minSdk. compileSdk defines the Android API level the project is compiled against. targetSdk indicates the API level the application is designed to run on, and minSdk specifies the minimum API level required to run the application. While updating the compileSdk allows the use of newer APIs, it's important to understand that these settings have different purposes and updating one doesn't automatically require updating the others.

Resolving the Build Failure

The solution is straightforward: update the Android SDK version used by the powersync_flutter_libs package to a newer version, such as API level 36. This can be achieved by modifying the build.gradle file within the powersync_flutter_libs package. Specifically, you need to locate the compileSdk setting within the android block of the build.gradle file and change its value to 36. After making this change, rebuild your Flutter project. This will ensure that the package is compiled against a compatible Android API level, resolving the dependency conflicts.

Step-by-Step Solution

1. Locate the build.gradle file: Navigate to the powersync_flutter_libs directory within your Flutter project's packages directory. Inside this directory, find the android directory, and within it, the build.gradle file. The exact path is usually something like packages/powersync_flutter_libs/android/build.gradle.
2. Modify the compileSdk: Open the build.gradle file in a text editor. Find the android block, and within that block, locate the compileSdk setting. It will look like compileSdk 32. Change the value to 36, so it reads compileSdk 36.
3. Sync Gradle: After modifying the build.gradle file, sync your project with Gradle. In Android Studio, you can usually do this by clicking the